This Fuseworks Dichroic Glass adds dimension, pattern, and surface variety to your fused glass projects. The photo shows the glass before and after firing. The top photo shows the raw glass piece you will receive, and the bottom photo shows what it looks like with a cap of clear glass fused to it.

Glass - Dichroic - Clear

What is COE and why is it important?

COE stands for
"coefficient of expansion". To put it simply, as glass heats up, it
expands and when it cools it contracts. The COE number tells us the
rate at which a particular glass expands and contracts. If you try to
fuse glass with mismatched COE numbers, the glass will crack as it
cools. So, it's critical to the success of your projects that you use
the same COE number for all the glass you are fusing in a project. But
don't worry; we've made it easy on you! All of our glass products are
90 COE so they combine safely.